Passing JSON data in Express Middleware

2018-07-11 03:40 Harry Cramer imported from Stackoverflow

I have the following route in my express app:

 app.post("/users/me/trackers/court_cases", caseValidator, DriversController.court_cases);

I would like to be able to pass information from my second middleware, caseValidator, to the third set of middleware. The second middleware currently fetches JSON data from a RESTful API, that I would like to pass along to the final route before sending it to the user.

Here's my current case validator function:

caseValidator = function(req, res, next){
    var case_id = req.body.case_id;

    var authOptions = {
        method: 'GET',
        url: `https://www.courtlistener.com/api/rest/v3/dockets/${case_id}/`,
        headers: {
            'Authorization' : "myauth"
        },
        json: true
    };

    var url = `https://www.courtlistener.com/api/rest/v3/dockets/${case_id}/`
    axios(authOptions)
        .then((response) => {
            console.log("success!")
            next();

            //// Pass in the JSON data to the next middleware?
        })
        .catch((error) => {
            res.status(400)
               .send(error)
        });
};

1 answer

answered 2018-07-11 05:12 Majid Sajadi

you can use req.someVar.

axios(authOptions)
   .then(response => {
        console.log("success!");
        req.someVar = response.data;
        next();
   })

then in next middleware you have access to that data.

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esp8286 is not connecting with my server, the error is

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var moscaSettings = {
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//   });

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  var ledCommand = '1';

  setInterval(function() {
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    console.log("MQTT server is ready on port %s", moscaSettings.port);
    console.log("HTTP Server is ready on pott %s", moscaSettings.http.port);
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process.on('uncaughtException', function (err) {
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and here is Esp8266 code

#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#include <EEPROM.h>

// Change the credentials below, so your ESP8266 connects to your router
const char* ssid = "AP1";
const char* password = "API@786_22#";


const char* mqtt_server = "192.168.1.75";
const char* clientname = "ESP-01-CLIENT1234";

//const int mqttPort = 3000;

WiFiClient espClient;
PubSubClient client(espClient);
// for data store intilization 

int address = 10;
int s1=11;
int s2=12;
char arrayToStore1[10];
char arrayToStore2[10];
char arrayToStore[10]; 


// Connect an LED to each GPIO of your ESP8266
const int ledGPIO2 = D2;
const int ledGPIO3 = D3;

// Don't change the function below. This functions connects your ESP8266 to your router
void setup_wifi() {
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void callback(String topic, byte* message, unsigned int length) {
  pinMode(ledGPIO3, OUTPUT);
  pinMode(ledGPIO2, OUTPUT);
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  // Feel free to add more if statements to control more GPIOs with MQTT

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void setup() {
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}

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 ----------------------------------- ---------- -------- ------ ------------------------------------------------------- 
  Name                                Method     Scheme   Host   Path                                                   
 ----------------------------------- ---------- -------- ------ ------------------------------------------------------- 
[..]
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[..]
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Router Match

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 [OK] Route "prezzi_listino" matches                                                                                    


+--------------+---------------------------------------------------------+
| Property     | Value                                                   |
+--------------+---------------------------------------------------------+
| Route Name   | prezzi_listino                                          |
| Path         | /prezzi/listino                                         |
| Path Regex   | #^/prezzi/listino$#sD                                   |
| Host         | ANY                                                     |
| Host Regex   |                                                         |
| Scheme       | ANY                                                     |
| Method       | ANY                                                     |
| Requirements | NO CUSTOM                                               |
| Class        | Symfony\Component\Routing\Route                         |
| Defaults     | _controller: AppBundle:Prices:pricesList                |
| Options      | compiler_class: Symfony\Component\Routing\RouteCompiler |
| Callable     | AppBundle\Controller\PricesController::pricesListAction |
+--------------+---------------------------------------------------------+

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In the auth.module :

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In the app.module :

imports: [
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But I get this error, I have no idea why ?

Use Firebase onRequest() or Express app.use() for the Slack API

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Use the @slack/interactive-message package with firebase-functions to listen and respond to Slack messages and dialogs.

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I'm not sure how to use the @slack/interactive-message listener with firebase.

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3) Something else?

Code

// Express
import express = require("express");
const app = express();
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app.use("*", cors);

// Firebase Functions SDK
import functions = require("firebase-functions");

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app.use("/app", slackInteractions.expressMiddleware());

// Express route
app.post("/go", (req, res) => {
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exports.helloWorld = functions.https.onRequest((_req, res) => {
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tl;dr

I'm new to the details of Express and using middleware. Examples of the @slack/interactive-message show...

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});

...and with Firebase Cloud Functions, this bit isn't relevant. I'm not sure how listeners, requests, and responses are integrated between Firebase and @slack/interactive-message

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Thanks in advance.
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